This application is related to co-pending U.S. Ser. No. 08/597,304 filed Feb. 6, 1996, entitled THREE-POSITION ACTUATOR PISTON ASSEMBLY AND ACTUATOR SYSTEM UTILIZING SAME and assigned to EATON CORPORATION, the assignee of this application.
1. Field of the Invention
The present invention relates to two-position shifting mechanisms and, in particular, splitter shifting mechanisms and controls for compound splitter-type transmissions and, more particularly, to splitter shifting mechanisms including a non-synchronized splitter clutch having increased backlash and a three-position splitter clutch actuator.
2. Description of the Prior Art
Compound change-gear transmissions of the splitter type and of the combined range-and-splitter type are well known in the prior art, as may be seen by reference to U.S. Pat. Nos. 4,290,515; 4,440,037; 4,754,665; 5,193,410; 5,272,939; 5,335,566; 5,368,145; 5,370,013 and 5,390,561, the disclosures of which are incorporated herein by reference.
The prior art splitter shift mechanisms typically included manually controlled two-position devices allowing selection of engagement of either a splitter-high or a splitter-low ratio, but not a splitter-neutral position. The prior art splitter shift mechanisms also typically utilized splitter jaw clutches having a relatively low backlash, as a true neutral position was not selectable, which provided a ratchet action (i.e., "buzzing") type of neutral if splitter shifts were attempted at sufficiently non-synchronous conditions to cause harsh shifting.
While widely used and commercially successful, the prior art splitter shifting mechanisms were not totally satisfactory, as the splitter clutches could be subject to undue wear and shifts outside of normally acceptable non-synchronous conditions could not be executed and completed if desirable.